Pull up revision 1.171 (via patch, requested by he):
Introduce the optional "teeny" variable in shlib_version, so that
we don't abuse the "minor" number to optionally include the
"teeny" number. Replace explicit ${SHLIB_MAJOR}.${SHLIB_MINOR}
with ${SHLIB_FULLVERSION}.

Patched per PR 7283; this causes shared libraries which depend on
other shared libraries to load against the ones just built when
DESTDIR is set (i.e. -L${DESTDIR}${LIBDIR} ), rather than what's
installed in /usr/lib (previous behavior definitely violated the
Principle of Least Astonishment!).